The transmission of video sequences sent by multimedia messaging in a communication network is problematic because of the heavy load it generates on this network in terms of bit rate. This load leads to congestion on the network, which is all the greater when video sequences are sent in multiple-broadcast mode to recipients with mailboxes that are not always situated on the same messaging servers. Furthermore, the video files that correspond to these sequences, because of their large size, congest the servers and the mailboxes of their recipients.
The practice of sending video by multimedia messaging does, however, remain commonplace because it is simple for the users of this messaging system, and enables the latter to consult the video sequences that have been transmitted to them over the communication network linked to this messaging, even when subsequent to this transmission they are no longer connected to the communication network.
The current techniques for transmitting video sequences by multimedia messaging do not effectively resolve the problems of congestion of networks and users' mailboxes, while maintaining the simplicity of use of the multimedia messaging systems for the users.
In practice, certain techniques for sending video sequences by multimedia messaging in a communication network use a system for filtering the attachments of multimedia messages sent over this network. The duly filtered attachments are stored in a storage space of the communication network, and replaced by a link to this storage space or to another device that can be used to recover the corresponding data.
These techniques do not allow a user to easily consult the video sequences of the messages that he receives, since the user must download these sequences before being able to read them. Furthermore, the user has no overview of the video sequences in the messages received, telling him the contents of these sequences before downloading them, which effectively obliges him to download them in order to know their contents. The pre-download knowledge of the content of the video sequences in the messages received would therefore limit the number of video sequences downloaded and therefore the problems of congestion.
Other techniques for sending video sequences by multimedia messaging in a communication network compress these video sequences before transmitting them to their recipients. These techniques limit the congestion of the networks and recipients' mailboxes, but do not allow the recipients access to all the video sequences that have been initially sent to them.
Another method that avoids the congestion of the user mailboxes with multimedia attachments is proposed in the application US 2005/0122345. For this, the method consists, based on a specific application installed on a user's messaging system, in coding the content of a message to be sent which contains a multimedia attachment, in the form of a low-resolution content corresponding to the attachment, this low-resolution content incorporating a resource address URL, “Uniform Resource Locator”. When a recipient receives such a message, he views the low-resolution content inserted into this message, and, if he wishes to see the corresponding multimedia content in full, all he has to do is to click this low-resolution content to access the server on which the corresponding multimedia content is stored in its original quality.
However, the decongestion of the networks and the mailboxes obtained by this method is limited: in practice when a recipient clicks on the resource address of a multimedia content that has been sent to him in low resolution, this recipient downloads a full version of this multimedia content. He will therefore have received and stored in all two files, a file corresponding to this low resolution multimedia content and a file corresponding to the full version of this multimedia content, instead of just one if he had directly received the full version of the multimedia content in the message addressed to him. Furthermore, this method requires a specific application on the messaging systems of the users sending video sequences.